After looking at all the events that happened, which one do you think is more powerful: science or superstition?
Superstition is more powerful because there are many examples where garlic flowers and the crucifix succeeds in preventing vampires from approaching. However, science in last section has unfortunately did not have the potential to save Lucy from Count Dracula. For example, in front of Lucy's tomb, when Lucy lures Holmwood to come near her, Van Helsing holds the crucifix which scares and surprises Lucy, the vampire. Moreover, in the last section, the garlic flowers evidently was very effective of preventing Dracula approaching while the blood transfusion was ineffective.

"As for Arthur, he seemed under a spell; moving his hands from his face, he opened wide his arms. She was leaping from them, when Van Helsing sprang forward and held between them his little golden crucifix. She recoiled from it, and, with a suddenly distorted face, full of rage, dashed past him as if to enter the tomb." (Stoker 188)

Why do you think Dracula is indomitable so far?
I think Dracula is indomitable so far because no one knows his exact identity. We are unaware of his full abilities and therefore cannot respond rapidly. We do not know what his actions cause, which led to Lucy's death. Now that the we are more familiar with vampires or Count Dracula, we should have a plan to what he is trying to do. Dracula is also indomitable because no one knows where he is heading to. If we were to know what his plans were, we would have prevented that from happening, but these irrelevant events confuse the characters and leave it unable to solve the cryptic puzzle.

"'In trance she died, and in trance she is Un-Dead, too.'" (Stoker 179)